Shareholders of UBS on Wednesday backed the board and management despite opposition due to the bank's involvement in various scandals, including a global probe into the largely unregulated $5.3tril-a-day foreign exchange market.

Big banks that rigged interest rates behaved in "brazen, flagrant" fashion, the head of the Commodities and Futures Trading Commission told CNBC on Wednesday, adding that imposing hefty fines were needed as a deterrent to bad behavior.